In this book authors studied the emission and excitation with XRD, SEM with relationship between emission intensity and concentration and chromatically nature for blue color. Inorganic phosphors have prospective application for blue lighting lamp industries applications. White LEDs emit white light at room temperature after the rare-earth-doped fluorescent powder is excited by blue light chips or ultraviolet chips. The realization of the photoluminescence phenomenon develops a new type of all-solid-state lighting source that is lauded as the fourth-generation lighting source due to its...